1. Field of Invention
The present invention discloses ratchet wrenches which include the useful and novel, additional structure of a universal joint (Herein after the terms universal joint or U-joint shall be considered to encompass constant velocity joints, block and pin Hooke's Type U-joints and swivel ball type U-joints.), integrally affixed to the rotatable member of the wrench; In one ratchet wrench, to the rotatable, dual-directional ratchet gear, and in the other wrenches, to the rotatable, dual-directional ratchet pawl.
The standard, block and pin type U-joint, which is a simple adaptation of the old Hooke's coupling, and is the prevalently used detachable U-joint in the hand tool industry, though described and illustrated as a viable structural option is, however, an unlikely candidate for mass production and use, primarily because of its excessive length and structural awkwardness in the application of locking means thereto.
As well, C V joints, primarily developed for the automotive industry, specifically for front-wheel drive vehicles, are optional U-joint structures that may potentially execute this invention. The Weiss Joint, the Rzeppa Joint and the Tracta Joint, patented in 1925, 1928, 1933 respectively, or various modifications of these U-joints in use today are however, like the block and pin type U-joint, also unlikely mass-producible candidates. This is primarily due to the fact that the slight benefit constant velocity provides in torqueing fasteners will not likely justify the increased complexity and cost and, as well, offset the minimal working angle, (around 15.degree.) characteristic of C V Joints.
The preferable U-joint for this application would comprise variations of the swivel ball type, which generally comprise a hinge pin and slot in the swivel ball to facilitate swiveling motion of the tang. This type of U-joint is widely used for power tool applications where added strength and compactness are added advantages. These U-joints generally provide a smaller working angle than the said block and pin type. A 30.degree. angle is typical and is defined as the degree of the swiveling angle off of the central axis of the socket. The invention disclosed would preferably utilize improved embodiments of this type of swivel U-joint, which in some cases would retain practically all of the strength per size ratio and, as well, add 15.degree. to the working angle, providing a full 45.degree. working angle. Also, this joint would be optionally lockable into a rigid, generally perpendicular axis with respect to the wrench head, since in the majority of times, the wrench user will not need the access advantage to normally accessible fasteners.
2. Prior Art
Prior art, being only remotely related to the subject invention, would include U.S. Pat. No. 4,114,401, in which a U-joint embodies an oscillating drive pin whereby a ball-receiving bore in a socket having diametrically opposing slots receives a swivel ball. The swivel ball comprises a pin rigidly extended both through its center and outward on both sides. Swiveling motion may be achieved as the ball may swing fore and aft in one E-W direction, while the pins in the slots enable the wrench tang's cylindrical coupling structure to swing in a correspondingly N-S direction, as the pins are guided in the slots. A major problem with the U-joint is the necessary apparatus that would be required to retain the ball and pin in its respective slotted holder during larger working angle torquing. Though the structure could withstand significant torque loads, it appears that the structure could only provide a maximum 20.degree. working angle, thus limiting its usefulness.
U.S. Pat. No. 3,855,884 discloses a locking U-joint and is cited because the subject invention includes various swivel joint, tang locking means. This patent comprises a socket sleeve which is axially slidable along an inner shaft portion central to the U-joint. The sleeve rim opposite the socket sleeve end abuts the rim of the cavity that retains the ball of the U-joint when the U-joint is locked; When the sleeve rim separates contact from the ball joint cavity rim, the ball joint and inner shaft cooperate as a normal U-joint. The locking means of the subject invention acts however, not upon a shaft means and joint cavity rim but directly upon the socket tang support means located at the opposite end of the socket drive tang. In addition, this patent is cited because it demonstrates the usefulness of a lockable U-joint means.
U.S. Pat. No. 4,936,701 depicts a useful U-joint comprising a rotatable sleeve whereby a wrench user, primarily of power wrenches, i.e., pneumatic, electric, etc., may grasp the joint while torquing a fastener, since the sleeve may remain stationary in the hand while the joint and applicable appendaged socket or socket tang and socket rotate. As in previously discussed U.S. Pat. No. 4,114,401, a swivel ball means is retained in cavity by a support means. However, the pin in this embodiment is fixed relative to the U-joint body and the ball joint is slotted to allow a rocking or swiveling motion upon the said pin support means. The working angle of this U-joint means is in the 30.degree. range and the ball joint is spring loaded to bias the socketing portion (i.e., tang or appendaged socket) to linear alignment to the core or central axis of the socket body.
From the above discussed prior art, it is evident that genuine efforts have been expended to produce an improved U-joint that is stronger, having a locking feature and also spring biasing the tang towards the linear structure of the U-joint. However the novel invention of including a permanently affixed U-joint within a ratchet wrench that includes the feature of either gradual to complete swivel tang lockability or quick, direct lockability is quite new to the hand tool field. As well, the above U-joints are cited as art that is distantly related to the basic subject invention.
It is an object of this invention to facilitate the introduction of a variety of potentially useful U-joints into either a dual-directionally rotatable ratchet gear means or into a dual-directionally rotatable ratchet pawl means. This improvement would greatly enhance the maneuverability of these wrenches, significantly lessening the need for detatchable U-joint adapters or U-joint sockets.
It is an object of this invention to provide the novel swivel tang ratchets with several tang position locking means so that when the swivelling tang is not needed the wrench user may turn, press or slide an atuator on the wrench, (preferably on the wrench head) that would enable one to engage this optional tang locking effect at will.
It is an object of this invention to provide the above discussed locking apparatuses with a variable or gradual tang locking position so that the total said working angle may be gradually reduced at will, to the desired angle.
It is also an object of this invention to provide the above improved ratchet wrenches with a biasing means so that the socket drive tang would continually be biased in a normal position, generally perpendicular to the wrench body.
It is an object of the invention to focus in on a preferable, swivel tang ratchet structure comprising a generally spherical swivel-jointed socket tang and a socket drive tang support means for said socket tang that is of a swivel pin type and is of few, uncomplex and reliable parts that is easily manufactured and may be rapidly assembled.